The present invention relates to a method and apparatus powered from the pressure side of a pump for cleaning a water pool, e.g., swimming pool.
The prior art is replete with different types of automatic swimming pool cleaners. They include water surface cleaning devices which typically float at the water surface and skin floating debris therefrom. The prior art also shows pool wall surface cleaning devices which typically rest at the pool bottom and can be moved along the wall (which term should be understood to include bottom and side portions) for wall cleaning, as by vacuuming and/or sweeping. Some prior art assemblies include both water surface cleaning and wall surface cleaning components tethered together.
The present invention is directed to a method and apparatus driven by a positive pressure water source for cleaning the interior surface of a pool containment wall and the upper surface of a water pool contained therein.
Apparatus in accordance with the invention includes: (1) an essentially rigid unitary structure, i.e., a cleaner body, capable of being immersed in a water pool and (2) a level control subsystem for selectively moving the body to a position either (1) proximate to the surface of the water pool for water surface cleaning or (2) proximate to the interior surface of the containment wall for wall surface cleaning.
The invention can be embodied in a cleaner body having a weight/buoyancy characteristic to cause it to normally rest either (1) proximate to the pool bottom adjacent to the wall surface (i.e., heavier-than-water) or (2) proximate to the water surface (i.e., lighter-than-water). With the heavier-than-water body, the level control subsystem in an active state produces a vertical force component for lifting the body to proximate to the water surface for operation in a water surface cleaning mode. With the lighter-than-water body, the level control subsystem in an active state produces a vertical force component for causing the body to descend to the wall surface for operation in the wall surface cleaning mode.
A level control subsystem in accordance with the invention can produce a desired vertical force component using one or more of various techniques, e.g., by discharging an appropriately directed water outflow from the body, by modifying the body""s weight/buoyancy characteristic, and by orienting hydrodynamic surfaces or adjusting the pitch of the body.
Embodiments of the invention preferably also include a propulsion subsystem for producing a nominally horizontal (relative to the body) force component for moving the body along (1) a path adjacent to the water surface when the body is in the water surface cleaning mode and (2) a path adjacent to the wall surface when the body is in the wall surface cleaning mode. When in the water surface cleaning mode, debris is collected from the water surface, e.g., by skimming either with or without a weir. When in the wall surface cleaning mode, debris is collected from the wall surface, e.g., by suction.
Embodiments of the invention are configured to be hydraulically powered, from the positive pressure side of an external hydraulic pump typically driven by an electric motor. This pump can comprise a normally available water circulation pump used alone or in combination with a supplemental booster pump. Proximal and distal ends of a flexible supply hose are respectively coupled to the pump and cleaner body for producing a water supply flow to the body for powering the aforementioned subsystems. The hose is preferably configured with portions having a specific gravity greater than 0.1 so that it typically lies at the bottom of the pool close to the wall surface with the hose distal end being pulled along by the movement of the body.
In preferred embodiments of the invention, the water supply flow from the pump is distributed by one or more control elements (e.g., valves) to, directly or indirectly, create water flows for producing vertical and horizontal force components for affecting level control and propulsion. A preferred propulsion subsystem is operable in either a normal state to produce a force component for moving the body in a first direction, e.g., forward, or a redirection (e.g.,backup) state to produce force components acting to move the body in a second direction, e.g., lateral and/or rearwardly. Water surface cleaning and wall surface cleaning preferably occur during the normal propulsion state. The redirection propulsion state assists the body in freeing itself from obstructions.
In a preferred heavier-than-water embodiment, a water distribution subsystem carried by the cleaner body selectively discharges water flows via the following outlets:
1. forward thrust jet
2. redirection or rearward (xe2x80x9cbackupxe2x80x9d) thrust jet
3. forward thrust/lift jet
4. vacuum jet pump nozzle
5. skimmer jets
6. debris retention jets
7. sweep hose
8. front chamber fill
The water flows discharged from these outlets produce force components which primarily determine the motion and orientation of the body. However, the actual motion and orientation at any instant in time is determined by the net effect of all forces acting on the body. Additional forces which effect the motion and orientation are attributable, inter alia, to the following:
a. the weight and buoyancy characteristics of the body itself
b. the hydrodynamic effects resulting from the relative movement between the water and body
c. the reaction forces attributable to sweep hose action
d. the drag forces attributable to the supply hose, debris container, etc.
e. the contact forces of cleaner body parts against the wall surface and other obstruction surfaces
A preferred cleaner body in accordance with the invention is comprised of a chassis supported on a front wheel and first and second rear wheels. The wheels are mounted for rotation around horizontally oriented axles. The chassis is preferably configured with a nose portion proximate to the front wheel and front shoulders extending rearwardly therefrom. The shoulders taper outwardly from the nose portion to facilitate deflection off obstructions and to minimize drag as the body moves forwardly through the water. Side rails extending rearwardly from the outer ends of the shoulders preferably taper inwardly toward a tail portion to facilitate movement of the body past obstruction surfaces, particularly in the water surface cleaning mode.
The body is preferably configured so that, when at rest on a horizontal portion of the wall surface, it exhibits a nose-down, tail-up attitude. One or more hydrodynamic surfaces, e.g., a wing or deck surface, is formed on the body to create a vertical force component for maintaining this attitude as the body moves through the water along a wall surface in the wall surface cleaning mode. This attitude facilitates hold down of the traction wheels against the wall surface and properly orients a vacuum inlet opening relative to the wall surface. When in the water surface cleaning mode, a hydrodynamic surface preferably rises above the water surface thereby reducing the aforementioned vertical force component and allowing the body to assume a more horizontally oriented attitude in the water surface cleaning mode. This attitude facilitates movement along the water surface and/or facilitates skimming water from the surface into a debris container.
A preferred cleaner body in accordance with the invention is configured with a hollow front fin extending above the water surface when the body is operating in the water surface cleaning mode. The fin has an interior chamber which can be water filled to provide a downward weight to help stabilize the operating level of the body near the water surface. In the wall surface cleaning mode, the water filled fin has negligible effect when the body is submerged but when the body climbs above the water surface, the weight of the filled fin creates a vertical downward force tending to cause the body to turn and re-enter the water.
A preferred cleaner body in accordance with the invention carries a water permeable debris container. In the water surface cleaning mode, water skimmed from the surface flows through the debris container which removes and collects debris therefrom. In the wall surface cleaning mode, water from adjacent to the wall surface is drawn into the vacuum inlet opening and directed through the debris container which removes and collects debris from the wall surface.
The debris container, in one embodiment, comprises a main bag formed of mesh material extending from a first frame. The first frame is configured to be removably mounted on the chassis and defines an open mouth for accepting (1) surface water flowing over a skim deck when in the water surface cleaning mode and (2) outflow from a vacuum path discharge opening when in the wall surface cleaning mode. In accordance with a significant feature of a preferred embodiment, the debris container may also include a second water permeable bag interposed between the vacuum path discharge opening and the aforementioned main bag. The second or inner bag is preferably formed of a finer mesh than the main bag and functions to trap silt and other fine material. The inner bag is preferably formed by a length of mesh material rolled into an essentially cylindrical form closed at one end and secured on the other end to a second frame configured for mounting adjacent to said vacuum path discharge opening. The edges of the mesh material are overlapped to retain fine debris in the inner bag.
The debris container, in another embodiment, comprises a main bag formed of mesh material containing one or more sheets or flaps configured to readily permit water borne debris to flow therepast into the bag but prevent such debris from moving past the sheets in the opposite direction. More specifically, first and second sheets of flexible mesh material are mounted in the bag such that one edge of the first sheet lies proximate to one edge of the second sheet. When the body is moving in its forward direction, pool water flowing into the bag acts to separate the sheet edges to enable debris to move past the edges into the bag. When the body is moving in a direction other than forward, e.g., rearward or laterally, water flow through the bag toward the mouth of the bag acts to close the sheet edges to prevent debris from leaving the bag.
The operating modes of the level control subsystem (i.e., (1) water surface and (2) wall surface) are preferably switched automatically in response to the occurrence of a particular event, such as (1) the expiration of a time interval, (2) the cycling of the external pump, or (3) a state change of the propulsion subsystem (i.e., (1) normal forward and (2) backup rearward). The operating states of the propulsion subsystem (i.e., (1) normal forward and (2) backup rearward) are preferably switched automatically in response to the occurrence of a particular event such as the expiration of a time interval and/or the interruption of body motion.
In a first disclosed embodiment (e.g., FIGS. 2, 3) using a heavier-than-water body, the level control subsystem in an active state produces a water outflow from the body in a direction having a vertical component sufficient to lift the body to the water surface for water surface cleaning.
In a second heavier-than-water embodiment (e.g., FIG. 17), the body is configured with at least one chamber which is selectively evacuated by an on-board water driven pump when the body is at the water surface to enable outside air to be pulled into the chamber to increase the body""s buoyancy and stability.
In a third heavier-than-water embodiment (e.g., FIG. 18), a body chamber contains an air bag coupled to an on-board air reservoir. When in a quiescent state, the chamber is water filled and the air bag is collapsed. In order to lift the body to the water surface, an on-board water driven pump pulls water out of the chamber enabling the air bag to expand to thus increase the body""s buoyancy and allow it to float to the water surface.
In a fourth embodiment (e.g. FIG. 19), the body is configured with at least one chamber which contains a bag filled with air when in its quiescent state. The contained air volume is sufficient to float the body to the water surface. In order to sink the body to the wall surface, the level control subsystem in its active state supplies pressurized water to fill the chamber and collapse the bag, pushing the contained air under pressure into an air reservoir.
Preferably all of the embodiments include a level override control for enabling a user to selectively place the level valve in either the wall surface cleaning mode or the water surface cleaning mode.
Although multiple specific embodiments of cleaner bodies and level and propulsion control subsystems in accordance with the invention are described herein, it should be recognized that many alternative implementations can be configured in accordance with the invention to satisfy particular operational or cost objectives. For example only, selected features from two or more embodiments may be readily combined to configure a further embodiment.
Among the more significant features is the inclusion of a motion sensor mechanism (e.g., FIGS. 21, 22) to sense when the rate of forward motion of the cleaner body diminishes below a certain threshold. This can occur, for example, when the body gets trapped behind an obstruction. By sensing the motion decrease, a redirection state can be initiated to move the body laterally and/or rearwardly to free it of the obstruction. This motion sensing feature has potential application in various types of pool cleaners regardless of whether they operate at both the water surface and wall surface. In accordance with a preferred embodiment, the motion sensor operates in conjunction with a periodic control device which alternately defines first and second conditions. Redirection is initiated when two conditions occur concurrently; i.e., the period control device defining the second condition and the motion sensor indicating that forward motion has diminished below the threshold.
In accordance with another significant feature, redirection is preferably accomplished by discharging the output of a jet pump (e.g., FIG. 22) in a direction substantially laterally with respect to the body.
In accordance with a further useful feature, a presdure indicator carried by the body is preferably coupled to the water distribute system to indicate to a user whether the pressure magnitude being delivered to the body is within an acceptable operating range.
In accordance with a still further feature (e.g., FIGS. 29, 32), a pitch control subsystem is carried by the body to selectively orient the body""s pitch to either (1) nose (i.e., front) up/tail (i.e., rear) down or (2) nose down/tail up. By selectively orienting the pitch of the body and providing forward propulsion, as from a single jet, the body can be driven either up to the water surface or down to the wall surface. The pitch control subsystem can be implemented by shifting weight and/or buoyancy between the front and rear of the body.